Surface area of parabolic sheet

Click For Summary
SUMMARY

The surface parameterized by r = (sin v, u, cos v) with v in the range of [-π/2, π/2] and u in [-1, 1] represents a half-shell of a cylinder with a radius of 1, not a parabolic sheet. The area of this surface is definitively calculated to be 2π. The confusion arises from the incorrect application of arc length methods to determine the surface area, which is not applicable in this context.

PREREQUISITES
  • Understanding of parameterized surfaces in multivariable calculus
  • Knowledge of cylindrical coordinates
  • Familiarity with surface area calculations
  • Basic concepts of arc length in calculus
NEXT STEPS
  • Study the derivation of surface area for parameterized surfaces
  • Learn about cylindrical coordinates and their applications in geometry
  • Explore the differences between arc length and surface area calculations
  • Investigate the properties of parabolic sheets and their surface area
USEFUL FOR

Students and professionals in mathematics, particularly those studying calculus and geometry, as well as educators teaching surface area concepts in multivariable calculus.

cscott
Messages
778
Reaction score
1
Am I correct in saying the surface parameterized by r = (sin v, u, cos v), v = [-pi/2, pi/2], u = [-1, 1] has an area of 2pi ?

I get something different by computing the arc length of the parabola within the bounds and multiplying by 2.

Which method is wrong?
 
Physics news on Phys.org
Sure, but that is not a parabolic sheet, it is the half-shell of a cylinder with radius 1..
 
Hmm.. I see. Thanks.
 

Similar threads

Replies
2
Views
2K
  • · Replies 33 ·
2
Replies
33
Views
3K
  • · Replies 20 ·
Replies
20
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
Replies
5
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K